Wednesday, 14 March 2018

Most U.S. electricity demand can be met by renewables

A
new study shows that up to 80 percent of the U.S. business and home energy
demands can be met through the use of renewable energy sources, especially wind
and solar power. The main limitation is with energy storage.

In
fact, it is theoretically possible to meet the entire U.S. energy demand
through renewable sources. However, the 100 percent aspirational target in
terms of electrical demand would require huge investment in investment in
greater storage capacity and power transmission capabilities. Efficient storage
solutions are essential with renewable sources due to the cycle of natural
variability.

The
assessment of energy comes from a collaborative effort from the University of
California, Irvine; the California Institute of Technology; and the Carnegie
Institution for Science. The group of scientists analyzed thirty-six years of
hourly U.S. weather data (collected during the period 1980 to 2015). This
analysis allowed the researchers to understand the primary geophysical barriers
in place that would affect supplying electricity to U.S. homes and businesses only
using solar and wind energy sources.

One
of the researchers, Professor Steven Davis explains to
Laboratory Manager magazine: “We looked at the variability of
solar and wind energy over both time and space and compared that to U.S.
electricity demand.”

He
proceeds to outline: “What we found is that we could reliably get around 80
percent of our electricity from these sources by building either a
continental-scale transmission network or facilities that could store 12 hours'
worth of the nation's electricity demand."

The
researchers said that such expansion of transmission or storage capabilities
would mean very substantial—but not inconceivable—investments. They estimated
that the cost of the new transmission lines required, for example, could be
hundreds of billions of dollars. In comparison, storing that much electricity
with today's cheapest batteries would likely cost more than a trillion dollars,
although prices are falling.